1. Technical Field
The present disclosure relates to a backlight unit and a liquid crystal display device having the same and, more particularly, to a backlight unit comprising a point light source, and a liquid crystal display device having the same.
2. Discussion of Related Art
Recently, flat panel display devices such as an LCD (liquid crystal display), a PDP (plasma display panel), an OLED (organic light emitting diode), and the like have been under development.
A liquid crystal display device includes a thin film transistor substrate, a color filter substrate, with a liquid crystal injected between both substrates to form a liquid crystal panel. Since the liquid crystal panel is a non-lighting element, a backlight unit for supplying light is provided in the rear of the thin film transistor substrate. Transmittance of light emitted from the backlight unit is determined by an arrangement of the liquid crystal.
A lamp as a line light source and a light emitting diode as a point light source have been widely used for the backlight unit, and local dimming that partially controls the light of a backlight unit according to a choice of a user has been applied thereto.
Generally, a light emitting diode is driven by a regulator or a pulse width modulation (PWM) integrated circuit (IC), and the like. To enlarge the size of the display device and more delicately represent a gray scale, the number of light emitting diodes should be increased and, accordingly, the backlight unit should have a plurality of power driving parts. The increase in the number of the power driving parts increases the overall cost, and raises a driving load of the backlight unit because of the requirement to control the plurality of power driving parts.